2- Chloropentanoic acid

An alternative synthesis starting from L-arginine, and involving the biotransformation of (S)-5-[(amino-iminomethyl) amino]-2-chloropentanoic acid (L-Cl-argi-nine) to (S)-5-amino-2-chloropentanoic acid (L-Cl-omithine), which then sponta-... 

Terpolymers of 3HB, 3HV, and 5-hydroxyvalerate (5HV) were obtained from R. eutropha grown with mixtures of 5-chloropentanoic acid and pentanoic acid [25], and PHAs containing 3HB units and 4-hydroxybutyrate (4HB) units have been produced by R. eutropha grown with mixtures of glucose and y-butyro-lactone [26]. The mole fraction of 4HB unit in these PHAs varied as a function of the concentration of carbon sources and pH of the culture. PHAs containing 5HV or 4HB were less crystalline and were biodegraded more readily than poly(3HB) or poly(3HB-co-3HV). 

The dianions of arylacetic acids 997 undergo alkylation reactions with l-bromo-3-chloropropane, with the resulting 5-chloropentanoic acids 998 cyclizing upon treatment with DBU providing a one-pot preparation of 3-aryltetrahy-dropyran-2-ones 999 (Scheme 259) <2003TL365>. 

C5H9Br 2-bromo-2-pentene 80204-19-9 383.15 33.811 1,2 5082 C5H9CI02 4-chloropentanoic acid 32607-54-8 440.14 38J63 2... 

The white crystalline diazoketone is dissolved in 10 ml of dry chloroform. Hydrogen chloride gas is bubbled slowly for 2 min into the solution that is cooled in ice. A spectrum of the product, 5-chloro-4-oxo-A -benzoxycarbonyl L-[5- C]norvaline-a-benzyl ester, should exhibit no diazo absorption. The chloroform is removed by flash evaporation and the residual material is suspended in 20 ml of 6 Af HCl and heated at 70° for 10 hr. The supernatant solution is decanted and replaced with 20 ml of 6 iV HCl, and the procedure is repeated until no insoluble material remains. The solutions are combined, and the products generated by removal of the protecting groups (benzyl alcohol, toluene) are removed by lyophilization the remaining colorless, moist powder may be dried under reduced pressure over PaO.-,. The net yield of L-2-amino-4-oxo-5-chloropentanoic acid hydrochloride is about 80% (49 mg, 0.24 mmole specific activity 1.16 Ci/mole). The chloroketone hydrochloride can be recrystallized from acetone-water to give the free base m.p. 151°-152° (dec.). 

Amino-5-hexynoic acid, 163 Aminonucleoside, 634 L-2-Amino-4-oxo-6-chloropentanoic acid, 416-417, see also Chloroketone 6-Aminopenicillanic acid, 536 m-(o-Aminophenoxyethoxy)benzami-dine, 118... 

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